I do agree that Toyota is taking a long time(over a decade) to redesign the current gen Tundra and other models, like the 4Runner. An everyone here has to admit that when the current Tundra came out it was a half ton game changer....As history shows, Toyota comes out with a design that will be relatively competitive for a decade, and then makes small refreshes from time to time. This saves them lots of money.
The new Tundra will be the same way I believe. When it comes out it will have a target on it's back and the big three will have to respond. It will also be around for a decade or more and after several years the big three will have caught up and will surpass it. Then the cycle will continue.
Ford changes designs and motors way sooner. They are able to do this because of the amount of market share (and profit) they have and because of their audience. People always want the latest and greatest. Problem is the latest is not always the greatest.